yeah turn up the pump speed, turn down the roomstat if you have one gravity hot water maybe?, if so totally inefficient and the only real saving would be to fit a new boiler, you could powerflush the system rads etc, but costs £.
How much is the gas bill per month? mines £22, but i'm a tight git
, yeah, make sure you is on a internet dual fuel account, is way cheaper, paying by direct debit.